* Regular unleaded gasoline: This was the most common fuel type for the 2012 Regal. The 2.4L Ecotec engine and the 2.0L turbocharged engine were designed to use regular unleaded.
* Premium unleaded gasoline: While not required for all engines, the 3.6L V6 engine recommended premium unleaded gasoline for optimal performance. Using regular in this engine might slightly decrease performance and fuel economy, but it likely wouldn't cause immediate damage.
Always check the owner's manual for the specific fuel recommendations for your particular 2012 Buick Regal model and engine.
